1. My input is PARMLIB member. It contains the list of files.
for ex: PRD.PARMLIB(MEMBER1)
MEMBER1 has the following data:
PRD.xxxx.FTP.DATA
PRD.xxxx.FTP.DATA
PRD.xxxx.FTP.DATA

Here xxxx is 4 letter code change from file to file. We don't know how many files we receive in a day and what files we receive. MEMBER1 may have 1 file or 2 files or 20 files or n files .

My task is: I need to take MEMBER1 as input and check each file inside MEMBER1 for particular data validations. If even one record in file is not qualifying my data checks, then that file should not be copied to output and only valid files should be copied to output file. Output file should contain only valid list of files.

By default MEMBER1 will be with fixed length of 80.
Files inside member will be in VB format.

Validations for ex: first 2 chars in file should be 'EC' and 3 to 6 chars should be same as 4 letter code of file.

you are right. But my difficulty is, to read file one by one and check the data, if data inside is not matching the criteria, even for one record, then I need to ignore that file. If the data valid for all records then I need to process the file for further actions.

It sounds pretty much like standard COBOL logic will work. If you have problems with the code once you've written it, let us know and we can make suggestions. However, this is a HELP forum, not a DO-YOUR-JOB-FOR-YOU forum so please do not ask for code unless you're willing to pay the professionals who respond on this forum their usual daily rate for work product (which typically is about 1000 U.S. dollars per day).

This should be the main body of your program.
Now, you have 2 smaller sections to take care of:
The "validate file" and the "output process" sections.

The "validate file" section could look like this:
At this time, the only thing you have is a dataset name (received from PARMLIB file)

Allocate the file.

scan the file and set a valid/not-valid fla (using "perform" again)

Free the file

The "output process" section will depend very much on how you plan to copy the files.
According to this sentence (I quote) "Output file should contain only valid list of files",
you just have to write the valid dataset name:

write to output file

There is now one section left: the "scan the file" section:

Open the file.

set flag to "valid"

Read one record.

at end of file, jump to point #8

Check record according to rules.

if valid, proceed to next record (point #3)

if not, set flag to "not-valid" and jump to point #8

Close the file.

return to caller (exit)

That may be the pseudo-code that describe your requirement.
You'll need now to translate that into cobol statements...
Good luck to you!